I doubt it. Remember that Google's real customer is not its user but companies running ads. Their ad revenue is directly correlated to the accuracy for its target audience. Think of every search result page from Google as a real estate. There's so much space that you can cram ads into, so showing ads to unnecessarily wider audience costs them precious space to make money. Google would lose a significant competitive edge if they stopped using personal tracking.
I believe the parent poster's point is that google searches are at the end of the purchase funnel when there's buying intent. As a result the click usually leads to the sale, and you can populate the ad based purely on the query. For instance I query "flower delivery Tampa FL" and the query tells me enough to populate ads.
